W3C home > Mailing lists > Public > public-swd-wg@w3.org > October 2008

Re: ISSUE-186: Last Call Comment: Mappings

From: Antoine Isaac <aisaac@few.vu.nl>
Date: Wed, 08 Oct 2008 15:43:36 +0100
Message-ID: <48ECC718.6070207@few.vu.nl>
To: SWD WG <public-swd-wg@w3.org>

Hi,

[I'm still officially offline, so it's not easy to react, these are just 
my two cents in case Sean and Alistair are interested]

> In addition, when mapping systems that are structurally heterogeneous
> (e.g., classification systems and thesauri), the links established
> through mappings have no hierarchical implications at all.
>
> Currently, skos:broader is used both for the hierarchical relationship
> between classes as well as between concepts. Mapping relations that are
> subproperties of skos:broader/skos:narrower are not able to sufficiently
> support interoperability between structurally heterogeneous systems.

Repeating what we discussed at our last F2F, I am still in favor of not 
having mapping properties sub-properties of paradigmatic ones :-)

> In addition, many different indicators of degree of mapping have been
> used in integrated vocabularies, e.g., major mapping, minor mapping,
> alternative mapping, and overlapping.  These may make the mapping
> properties even more complicated. The solution here might again be to
> extend mapping properties.

This precise issue has been discussed when we made the decision to have 
a mapping vocabulary in SKOS (ISSUE-39 and related ones, sorry I don't 
have time and network to make more citations). In the previous SKOS 
mapping voc there was such major/minor overlap property, but it was 
arbitrary. Indeed having such specializations in the standard would 
cause raise many different possible choices, some potentially 
conflicting (is an "50% broader match" a specific case of "broad match" 
or "related match" or of a new mapping property?). It is therefore left 
to applications to specialize the mapping properties according to their 
needs.
Also, when mapping "meta-properties" become too complex, we can point 
users to other patterns, like the alignment format used in the context 
of the Ontology Alignment Evaluation Initiative [1]. There, mappings are 
somehow reified, which allows to annotate them. And the pattern is 
compatible with the use of SKOS mapping properties (these are then 
annotations which specify the semantic value of the mapping)

Cheers,

Antoine

[1] http://oaei.ontologymatching.org/2008


> ISSUE-186: Last Call Comment: Mappings
>
> http://www.w3.org/2006/07/SWD/track/issues/186
>
> Raised by: Sean Bechhofer
> On product: SKOS
>
> Raised by Michael Panzer [1]:
>
> 6. Mappings
> -----------
>
> The problem of restricting SKOS to one-to-one mappings has already been
> raised as ISSUE-131. We share the concerns expressed there.
>
> We also see potential problems in deriving the mapping relations
> skos:broadMatch and skos:narrowMatch from skos:broader and
> skos:narrower. In ISO standard and current practices many multilingual
> thesauri did not use broader or narrower to indicate the mapping
> relations. SKOS should revisit those standards and follow the current
> standards' development to make sure SKOS is consistent in representing
> the indicators used by standards (and the thesauri following those
> standards) for so many years.  
>
> In addition, when mapping systems that are structurally heterogeneous
> (e.g., classification systems and thesauri), the links established
> through mappings have no hierarchical implications at all.
>
> Currently, skos:broader is used both for the hierarchical relationship
> between classes as well as between concepts. Mapping relations that are
> subproperties of skos:broader/skos:narrower are not able to sufficiently
> support interoperability between structurally heterogeneous systems.
>
> In addition, many different indicators of degree of mapping have been
> used in integrated vocabularies, e.g., major mapping, minor mapping,
> alternative mapping, and overlapping.  These may make the mapping
> properties even more complicated. The solution here might again be to
> extend mapping properties.
>
> [1] http://lists.w3.org/Archives/Public/public-swd-wg/2008Oct/0061.html
>
>
>
>
>
>
>   
Received on Wednesday, 8 October 2008 14:47:59 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 8 October 2008 14:48:15 GMT